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(Germany) (for details see original references listed in Table 1
and Voelker et al. [2009]). The benthic
δ
Greenland Ice Sheet Project 2 (GISP2) ice core chronology
either by direct tuning or by calibrating accelerator mass
spectrometry
14
C ages with the Hughen et al. [2004] data.
Because the focus of this study is on amplitudes and timing
between the different records rather than absolute ages,
GISP2-linked chronologies were kept instead of revising to
North Greenland Ice Core Project (NGRIP) or Hulu Cave-
based calibration data. Thus, data of core MD95-2042 are
shown on the Shackleton et al. [2000] chronology using the
GISP2 correlation points, while cores MD99-2334K, MD99-
2339, MD03-2698, and SU92-03 are shown on their original
published timescales (Table 1). For MIS 3 data of core
MD01-2444, correlation points to the GRIP chronology
given by Vautravers and Shackleton [2006] were converted
to GISP2-based ages. However, the alkenone-derived SST
record of this core is shown on the age scale in the work of
Martrat et al. [2007], which is related to the NGRIP ice core
on the GICC05 (back to 60 ka) and ss09sea chronologies for
the last 120 kyr. The age model of core MD95-2041, except
for the MIS 2 section, where the age model of Voelker et al.
[2009] is applied, was established by correlating its G. bul-
loides
18
O record of core
MD95-2040 combines values corrected to the Uvigerina
level of the following foraminifer species: Cibicidoides
wuellerstorfi, Cibicidoides kullenbergi, Cibicidoides sp.,
Uvigerina peregrina, Uvigerina pygmea, Melonis sp., and
Globobulimina af
nis (only in MIS 6). Correction factors are
those listed by de Abreu et al. [2005]. The benthic
δ
13
C
record, on the other hand, only includes Cibicidoides-derived
values. For details on the MD01-2443 benthic records, the
reader is referred to the work of Martrat et al. [2007].
Following the work of Voelker et al. [2009], planktic
foraminifer species for which stable isotope data were ob-
tained for the MIS 3, 4, and 6 intervals are Globigerina
bulloides, Globigerinoides ruber white, Neogloboquadrina
pachyderma (r) or (s), Globorotalia in
ata, Globorotalia
scitula, and Globorotalia truncatulinoides (r) or (s). G. trun-
catulinoides (s) values are generally only shown for MIS 4
when this species dominates over the right-coiling variety in
the assemblage. For the MIS 3 section of core MD99-2339,
on the other hand, samples of either coiling direction were
analyzed, and a combined record, sometimes based on mean
values from double measurements, is shown. The combined
δ
18
O record to the one of core MD95-2042 taking the
positions of percent N. pachyderma (s) maxima that are
marking Heinrich stadials into account. The percent N. pa-
chyderma (s) maxima were especially relevant to identify
Heinrich stadials 3 to 5 and 8. Also, the age model for the
MIS 4 section of core MD99-2336 is based on correlating its
G. bulloides
δ
18
O and
13
C records for these species, which cover calci-
δ
fication depths from 50 to 400 m [see Voelker et al., 2009,
Table 4], are used to reconstruct conditions in the upper
water column during the respective glacial intervals. Follow-
ing the work of Ganssen and Kroon [2000], the
18
O differ-
ence between G. bulloides and G. inflata is used to evaluate
seasonality. As discussed by Voelker et al. [2009], none of
the planktic foraminifer isotope values are corrected because
regional correction factors do not exist, yet.
Data and age models of cores MD95-2040, -2041, MD99-
2336, -2339, MD01-2443, and -2444 used in this study are
available from the WDC-Mare through the parent link http://
doi.pangaea.de/10.1594/PANGAEA.737449.
18
O record [Llave et al., 2006] to core MD95-
2042, while the MIS 2 section follows the work of Voelker et
al. [2009].
Data of core MD01-2443 are shown on the age model
established by Tzedakis et al. [2009], who, following the
work of Shackleton et al. [2000], tuned the benthic
δ
δ
18
O
δ
record of this core to the
D record of the EPICA Dome C
(EDC) ice core on its EDC3 chronology. Salgueiro et al.
[2010] recently published a chronology of core MD95-
2040 back to the top of MIS 6. However, when compiling
the figures for this chapter, we noted that with the Salgueiro
et al. [2010] age model, the percent N. pachyderma (s)
maximum/SST minimum of Heinrich stadial 8 is signi
δ
4. CHRONOSTRATIGRAPHIES
For many of the cores, for which data from the last glacial
cycle are shown, the (initial) age model was linked to the
cantly
older than the one in core MD95-2042. Thus, a revised
Figure 3.
(opposite) Latitudinal gradients in the abundance of percent Neogloboquadrina pachyderma (s) (percent) (left column) and sea
surface temperature (SST) derived from planktic foraminifer assemblages (°C) (right column) over the last 80 kyr. SST values refer to
summer (black) or August (gray). The transect from north to south consists of cores SU92-03 [Salgueiro et al., 2010], MD99-2331
[Sánchez-Goñi et al., 2008], MD95-2040 [de Abreu et al., 2003] with SST recalculated for this study, MD95-2041 [Voelker et al., 2009, this
study], MD95-2042 with SST recalculated based on counts of Cayre et al. [1999] (black SST line and percent N. pachyderma (s)) and SST
data from Sánchez-Goñi et al. [2008] (gray line), MD01-2444 [Vautravers and Shackleton, 2006] with SST recalculated for this study, and
MD99-2339 [Voelker et al., 2006, 2009, this study]. Note the change in the percent N. pachyderma (s) scale for core MD99-2339 to adjust
for the gradient of more than 90% in the north to the maxima of just 16% in the south. A shift by 2°C in the SST scale is also observed for
core MD95-2041 and the records below. Gray bars mark Heinrich stadials.
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